Lesson 10

Question 1

what is risk ?

Answer 1

a measure of the probability and severity of harm under DEFINED CONDITIONS OF EXPOSURE

Question 2

what is the risk of dying from cancer in canada ?

Answer 2

30%

Question 3

what is the risk of dying from heart disease in canada ?

Answer 3

19.7%

Question 4

what does risk depend on ?

Answer 4

behavior

Question 5

what are 4 diseases in which risk of death depends on diet ?

Answer 5

cancer
heart disease
stroke
diabetes

Question 6

what is the rate of risk of acquiring a foodborne illness in Canada per year ?

Answer 6

1/8 people so 12.5%

Question 7

what is chronic sequelae ?

Answer 7

chronic complications following an acute illness

Question 8

what is a risk in foodborne illnesses in 2-3% of cases ?

Answer 8

chronic sequelae which may be more detrimental than the acute disease

Question 9

what are pathogens ?

Answer 9

microorganisms capable of causing disease

Question 10

are all bacteria pathogenic ?

Answer 10

no

Question 11

what are 5 classes of people that are more susceptible to pathogens ?

Answer 11

very young
very old 
pregnant women 
malnourished
compromised immune systems

Question 12

what are foodborne illnesses ?

Answer 12

illness transmitted to human beings through food and water, caused by an infectious agent (foodborne infection) or a poisonous substance (food intoxication, so by an agent’s toxic secretions)

Question 13

what are the two ways foodborne illnesses are transmitted to humans ?

Answer 13

through food and water

Question 14

foodborne infections are caused by eating foods contaminated by _____

Answer 14

live pathogens

Question 15

what are 4 symptoms of foodborne infections ?

Answer 15

abdominal cramps
fever
vomiting
diarrhea

due to the pathogens proliferating in the GI tissue

Question 16

what is food intoxication caused by ?

Answer 16

eating foods containing natural toxins produced by pathogens (meaning the pathogens do not necessarily need to be in there)

enterotoxins (infect GI)
or neurotoxins (infect nervous system)

Question 17

how long do you get sick once contaminated food is consumed ? what does it depend on

Answer 17

onset of symptoms depends on the time it takes for the pathogens to grow and proliferate in the small intestines

Question 18

how long is the onset of symptoms for food intoxication ?

Answer 18

within a few hours

Question 19

what are 4 classes of pathogens in food ?

Answer 19

foodborne bacterial pathogens

foodborne viral pathogens

bacterial toxin producers

other microorganism producing toxins

Question 20

what are 4 exampels of foodborne bacterial pathogens ?

Answer 20

campylobacter jejuni
salmonella
E. coli
listeria

Question 21

what is an example of a foodborne viral pathogen ?

Answer 21

Norwalk virus

Question 22

what are 2 examples of bacterial toxin producers ?

Answer 22

staph aureus

clostridium botulinum

Question 23

what are 2 examples of other microorganisms producing toxins ?

Answer 23

fungi: aflatoxin
algae: marine toxins

Question 24

how does sex happen for bacteria ? what is it called ?

Answer 24

uncoupled sexual production

pili extend to other cells, permitting exchange of genetic information, permitting an exchange of genes from a donor cell to a recipient cell

Question 25

explain bacterial reproduction

Answer 25

there is none. two cells come together, modify, and then go apart.

Question 26

when does bacterial uncoupled sexual production become a problem ?

Answer 26

when bacteria exchange genes for antibiotic resistance (esp inside of livestock)

Question 27

what are 2 ways to contaminate food with campylobacter jejuni ?

Answer 27

eating undercooked meat improperly handling poultry

Question 28

what is a dangerous practice when it comes to rinsing raw poultry? what does it put at risk for ?

Answer 28

washing or rinsing raw poultry before cooking it is potentially unsafe bc of the splashing of contaminated water, which may lead to the transfer of pathogens to other foods and kitchen surfaces

Question 29

what 3 diseases are related to campylobacter jejuni ?

Answer 29

Guillain-Barre syndrome (neuromuscular paralysis) reactive arthritis IBS

Question 30

which neurodegenerative disease is linked to campylobacter jejuni and what is the association ?

Answer 30

Guillain-Barre | 1 case for GBS for every 1000 of campylobacteriosis

Question 31

what percentage of people with GBS have evidence of recent campylobacter infection ?

Answer 31

40%

Question 32

can patties be cooked raw ?

Answer 32

no

Question 33

why can't patties be cooked raw, but steaks can ?

Answer 33

because steaks : pathogens stay on the surface, so searing it is fine but for patties, the pathogens are mixed throughout the grinding process

Question 34

what are two things that happen in patties during the grinding process ?

Answer 34

increase the surface area for protein-rich tissue for microbes to grow + supplies oxygen for microbes to grow and multiply

Question 35

what is a main cause of E.coli infections ?

Answer 35

mechanically tenderized meat (incising the surface of meat to tenderize it)

Question 36

what is a way of reducing risk of E. coli

Answer 36

indicating when a meat has been mechanically tenderized

Question 37

where is listeria found ?

Answer 37

in soil and water

Question 38

what are two ways listeria adapted to increase its pathogenicity?

Answer 38

forms biofilm on surfaces | can grow and multiply in refrigerator

Question 39

which pathogen can find its way into packaged food ?

Answer 39

listeria

Question 40

what is biofilm

Answer 40

sticky, slimy film that adheres on surfaces

Question 41

what is listeria killed by ?

Answer 41

pasteurization and cooking

Question 42

what happened in the listeriosis outbreak in Ontario ?

Answer 42

contaminated after factory cooking lunch meats and hot dogs

Question 43

why can listeria infection risk increase with using precut lettuce ?

Answer 43

cutting liberates nutrients previously confined to insides of plant cells, and these released nutrients become food for pathogens to grow + precut lettuce hard to wash properly

Question 44

what are 3 words for the Norwalk virus ?

Answer 44

norovirus stomach flu winter vomiting disease

Question 45

what are 4 symptoms of the Norwalk virus ?

Answer 45

vomiting diarrhea abdominal pain body aches

Question 46

what is the contagiousness and duration of Norwalk virus symptoms ?

Answer 46

very contagious, but short lived symptoms (less than 2 days)

Question 47

what are 3 ways to transmit the Norwalk virus ?

Answer 47

contaminated food contaminated water human contact

Question 48

what areas of the body is staph aureus commonly found (2)

Answer 48

hands and nose

Question 49

explain the mechanism of action of the staph aureus

Answer 49

cooked food contaminated w staph aureus when served by a person with unwashed hands bacteria multiply and produce a toxin when leftover food is reheated, it destroys the bacteria but not the toxin

Question 50

how long does it take for the staph aureus symptoms to occur ? what are they

Answer 50

nausea, vomiting, stomach pain 1-6 hours after consumption

Question 51

what does clostridium botulinum produce ?

Answer 51

botulinum

Question 52

what is the most poisonous substance known to man ?

Answer 52

botulinum

Question 53

where is botulinum found in nature ?

Answer 53

in spores in plants and in soil

Question 54

which toxin doesn't need oxygen to multiply ?

Answer 54

botulinum

Question 55

what is the most common cause of intoxication from botulinum?

Answer 55

home canned foods and homemade garlic and oils stored at room temperature

Question 56

what kind of toxins do fungi produce ?

Answer 56

mycotoxins

Question 57

what is aflatoxin ?

Answer 57

a type of mycotoxin, produced by fungi in mouldy crops

Question 58

what legume contains trace amounts of aflatoxin ?

Answer 58

peanuts

Question 59

aflatoxin may cause which disease ?

Answer 59

liver cancer

Question 60

what regions in the world are especially vulnerable to liver cancer due to aflatoxin ?

Answer 60

africa (40%) east asia western pacific (north america and europe 0%)

Question 61

what is the most well known algae toxin ?

Answer 61

algae which produce toxic red tides

Question 62

how can climate change increase toxic red tides ?

Answer 62

favoring the growing conditions

Question 63

what is a pesticide ?

Answer 63

any chemical used to control unwanted insects, fungi, weeds

Question 64

where do 99% of deaths due to pesticides occur ?

Answer 64

in developing countries

Question 65

what are the three modes of entry of pesticides ?

Answer 65

inhalation dermal contact ingestion

Question 66

who is at most risk of dying from pesticides ?

Answer 66

those who apply it

Question 67

what is the reference dose ?

Answer 67

a function of the dose at which no effects from pesticides are observed, and then divided to account for more vulnerable people and amount of evidence

Question 68

what is the risk of pesticides dependent on ?

Answer 68

where you live

Question 69

what is the main factor of food preservation techniques ?

Answer 69

temperature (heat or cold)

Question 70

what is irradiation ?

Answer 70

use of low dose radiation to kill pathogens on food

Question 71

irradiation is permitted by Health Canada on which 3 foods ?

Answer 71

spices onions and potatoes wheat flour

Question 72

what international symbol do irradiated foods have ?

Answer 72

radura

Question 73

what does irradiation prevent on onions and potatoes ?

Answer 73

premature sprouting

Question 74

is irradiation really related to cancer ?

Answer 74

no ! most potential human hazards are false alarms leading to overregulation

Question 75

is irradiation safe ?

Answer 75

yes

Question 76

what are nitrites ?

Answer 76

an additive used to preserve lunch meats and sausages

Question 77

are nitrites safe ?

Answer 77

they are considered a necessary evil (risk-risk tradeoff): they are carcinogenic but prevent botulism